The standard entropies of CO2(g), C(s) and O2(g) are 213.5, 5.690 and 205 JK–1 respectively. The standard entropy of formation of CO2(g) is
(1) 1.86 JK–1
(2) 1.96 JK–1
(3) 2.81 JK–1
(4) 2.86 JK–1
Equal volumes of monoatomic and diatomic gases at same initial temperature and pressure are mixed. The ratio of specific heats of the mixture (Cp/Cv) will be [AFMC 2002]
(1) 1
(2) 2
(3) 1.67
(4) 1.5
The unit of entropy is -
1. J mol–1
2. JK mol–1
3. J mol–1 K–1
4. J–1 K–1 mol–1
The entropy changed involved in the conversion of 1 mole of liquid water at 373 K to vapour at the same temperature will be [MP PET 2002]
(1) 0.119 kJ
(2) 0.109 kJ
(3) 0.129 kJ
(4) 0.120 kJ
When a liquid boils, there is [JIPMER 2002]
(1) An increase in entropy
(2) A decrease in entropy
(3) An increase in heat of vaporization
(4) An increase in free energy
The work done to contract a gas in a cylinder, is 462 joules. 128 joule energy is evolved in the process. What will be the internal energy change in the process [MP PMT 2003]
(1) + 590 joules
(2) – 334 joules
(3) + 334 joules
(4) – 590 joules
For a carnot engine, the source is at 500 K and the sink at 300 K. What is efficiency of this engine
(1) 0.2
(2) 0.4
(3) 0.6
(4) 0.3
From Kirchhoff's equation which factor affects the heat of reaction [MP PMT 1990]
1. Pressure
2. Temperature
3. Volume
4. Molecularity
The absolute enthalphy of neutralisation of the reaction will be [CBSE PMT 2005]
(1) Less than –57.33 kJ mol–1
(2) –57.33 kJ mol–1
(3) Greater than –57.33 kJ mol–1
(4) 57.33 kJ mol–1
The heat of transition (ΔHt) of graphite into diamond would be, where
[Pb. PET 1985]
(1)
(2)
(3)
(4) None of these